Method of charging leaching vats

ABSTRACT

A method and apparatus for charging a leaching vat. Shallow transverse strips of the charging material are deposited on the bottom of the vat in side-by-side relation across one-half of the vat and from one end of the vat to the other, this process then being repeated for the other half of the vat. The foregoing procedure results in the deposition of a shallow layer of the charging material on the bottom of the vat, and is repeated to form second and subsequent layers, until the vat is filled to the desired level. The end result is a charge which is substantially uniform throughout the vat, with substantially no impervious concentrations of fines.

United States Patent Inventor Appl. No. Filed Patented Assignee METHODOF CHARGING LEACHING VATS Primary Examiner-Richard E. AegerterAttorney-Harris, Kiech, Russell and Kern ABSTRACT: A method andapparatus for charging a leaching vat. Shallow transverse strips of thecharging material are deposited on the bottom of the vat in side-by-siderelation across one-half of the vat and from one end of the vat to theother, this process then being repeated for the other half of the vat.The foregoing procedure results in the deposition of a shallow layer ofthe charging material on the bottom of the vat, and is repeated to formsecond and subsequent layers, until the vat is filled to the desiredlevel. The end result is a charge which is substantially uniformthroughout the vat, with 2 Claims, 8 Drawing Figs.

US. Cl 198/101,

214/18 Int. Cl B65g 37/00 Field of Search 214/18;

198/101 substantially no impervious concentrations of fines.

A I A 1 METHOD OF CHARGING LEACI-IING VATS CROSS-REFERENCE TO RELATEDAPPLICATION This application is related to my copending patentapplication Ser. No. 689,393, filed Dec. 11, 1967, and entitled AP-PARATUS FOR DEPOSITING MATERIAL IN AND REMOVING IT FROM ELONGATEDPROCESSING ZONES.

BACKGROUND OF INVENTION The present invention relates in general to amethod and apparatus for depositing material on a surface havingtransversely spaced sides and longitudinally spaced ends. For example,such surface may be the bottom of a vat or tank used to leach ores, suchas low-grade copper ores, or other materials having components to bereclaimed.

In charging leaching vats with ores or other materials with conventionalmethods and apparatuses, concentrations of fines are frequentlyproduced, usually as the result of depositing the material in onelocation in the vat for too long a period of time. When this is done, alarge conical pile is formed down which fractions of differentcoarsenesses slide at different rates so that concentrations of coarseparticles and fines are formed.

When a leaching liquid is introduced into a vat charged in the foregoingconventional manner, it penetrates the concentrations of finesinadequately, or not at all, such concentrations being relatively.impervious to the leaching liquid. The end result is that a substantialproportion of the ore or other material in the vat is untouched by theleaching liquid. This is obviously undesirable since it means the lossof a substantial proportion of the component or components beingreclaimed form the material with which the vat is charged.

SUMMARY AND OBJECTS OF THE INVENTION With the foregoing background inmind, a primary object of the invention is to provide a method of andapparatus for depositing material on a surface, such as the bottom of aleaching vat, uniformly in a substantially homogeneous charge having noconcentrations of fines which are impermeable to a treating liquid, suchas a leaching liquid. Consequently, the entire charge is accessible tothe treating liquid so that, in the case of a leaching operation, thedesired component or components may be leached from the entirecharge,'which is an important feature of the invention.

More particularly, an important object of the invention is to depositthe material in question on the desired surface in a succession ofrelatively thin or shallow layers'each composed of a plurality of stripsof the material in side-by-side relation. With this procedure, there issubstantially no possibility of fines concentrating in quantitiessufficient to prevent penetration by a treating liquid, which is animportant feature.

Another important object of the invention is to form each shallow layerof the charging material on the desired surface by depositing transversestrips of the material in side-by-side relation on half the area of thesurface, proceeding from one end of the surface to the other, and bythen depositing transverse strips of the material in side-by-siderelation on the other half of the area of the surface, proceeding fromthe other end of the surface to the one end thereof.

Still another important object is to deposit adjacent transverse stripson each half of the area of the surface in opposite directions. Moreparticularly, an object in this connection is to deposit transversestrips in side-by-side relation on one half the area of the surface byproceeding back and forth in opposite transverse directions between oneside of the surface and the center thereof, and to deposit transversestrips in sideby-side relation on the other half of the area of thesurface by proceeding back and forth in opposite transverse directionsbetween the other side of the surface and the center thereof. Anotherrelated object is to proceed longitudinally of the surface in onedirection in depositing material on one half thereof, and to proceedlongitudinally of the surface in the other direction in depositingmaterial on the other half thereof. With this procedure, the apparatusfor depositing the transverse strips of material returns to its startingposition after having deposited a complete shallow layer on the surface,or on a preceding layer thereon, which is an important feature.

Yet another important object of the invention is to provide an apparatusfor carrying out the foregoing method which includes a bidirectionalshuttle conveyor above and extending transversely of the surface andbidirectionally shiftable both laterally and longitudinally of thesurface.

More particularly, an object of the invention is to provide a transverseshuttle conveyor the discharge end of which is transversely shiftableback and forth across the corresponding half of the area of the surface,between the center of the surface and the corresponding half of the areaof the surface, between the center of the surface and the correspondingside thereof, as the shuttle conveyor is shifted longitudinally of thesurface in a step-by-step manner from one end thereof to the other.Since the shuttle conveyor is bidirectional, one end acts' as thedischarge end when depositing material on one half of.

the area of the surface, and the other end acts as the discharge endwhen depositing material on the other half of the area of tee surface,the shuttle conveyor being displaced step by step in one longitudinaldirection when depositing material on one half, and being displaced stepby step longitudinally in the other direction when depositing materialon the other half.

A further object of the invention is to provide feed conveyor means,shiftable longitudinally of the surface with the shuttle conveyor in astep-by-step manner, for feeding the material to the shuttle conveyorirrespective of the direction of transverse movement of the shuttleconveyor.

More particularly, an additional object of the invention is to provide afeed conveyor means which includes a unidirectional feed conveyor aboveand extending transversely of the surface and having a discharge endabove the shuttle conveyor, the feed conveyor being shiftabletransversely of the surface to position its discharge end on the side ofthe center of the surface opposite the half of the surface being chargedby the shuttle conveyor.

The foregoing objects, advantages, features and results of the presentinvention, together with various other objects, advantages, features andresults thereof which will be evident to those skilled in the art towhich the invention relates, may be achieved with the exemplaryembodiment of the invention illustrated in the accompanying drawings anddescribed in detail hereinafter.

DESCRIPTION OF DRAWINGS In the drawings:

FIG. 1 is a fragmentary, semidiagrammatic, plan view of a materialdepositing apparatus of the invention;

FIG. 2 is an enlarged, fragmentary sectional view taken as indicated bythe arrowed line 2-2 of FIG. 1;

FIG. 3 is a further enlarged, fragmentary plan view taken as indicatedby the arrowed line 3-3 of FIG. 2;

FIG. 4 is a diagrammatic view illustrating the manner in which materialis deposited on the bottom of a leaching vat in accordance with theinvention;

FIGS. 5 and 6 are sernidiagrammatic, transverse sectional viewsillustrating the manner in which transverse strips of material aredeposited in side-by-side relation on one half of the bottom of theleaching vat; and

FIGS. 7 and 8 are view's similar to FIGS. 5 and 6, but illustrating themanner in which transverse strips of material are deposited inside-by-side relation on the other half of the bottom of the leachingvat.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT OF THE INVENTIONReferring initially to FIG. I of the drawings, illustrated therein inplan is an elongated processing or treating zone It) in which anydesired material may be subjected to any suitable process or treatment.For convenience in disclosing the invention, the processing zone will beconsidered hereinafter as suitable for leaching such materials as ores,e.g., low-grade copper ores. However, the invention is not limitedthereto, and is applicable to any situation wherein uniform depositionof a material to obtain a substantially homogeneous mass is required.

With the foregoing exemplary utilization of the invention in mind, theprocessing zone 119 may comprise a series of leaching tanks or vats 12arranged in what will be regarded herein as an end-to-end relation as amatter of convenience, although the vats are shown as approximatelysquare. Running on tracks 14 on opposite sides of and extendinglongitudinally of the series of leaching vats 12 constituting theprocessing zone 10 is a material depositing apparatus 16 of theinvention for charging the leaching vats. The material depositingapparatus 16 has the form of a bridge which spans the series of leachingvats 12 and is carried at its ends by the tracks 14. (Laterallyoutwardly of the respective tracks 14 are longitudinal tracks 18 for anunloading apparatus, not shown, similar to that disclosed in myaforementioned copending application, such unloading apparatus beingused to remove the material from the leaching vats 12 after the desiredcomponent or components have been leached therefrom.)

Generally, the material depositing apparatus 16 is similar to thatdisclosed in my aforementioned copending application so that only thefeatures thereof essential to the present invention will be described indetail herein. Briefly, the material depositing apparatus 16 comprises abidirectional shuttle conveyor 20 above and extending transversely ofthe series of leaching vats l2, suitable bidirectional driving means,not shown, being provided to drive the shuttle conveyor 20 in oppositedirections so that either end thereof may be its discharge end. Theshuttle conveyor 20, which has a length less that the width of theseries of leaching vats 12, is shiftable transversely of the series ontracks 22, best shown in FIG. 2 of the drawings. The material dispensingapparatus 16 also includes a feed conveyor means 24 for feeding thedesired material to the shuttle conveyor 20, the feed conveyor meansincluding a unidirectional feed conveyor 26 above and extendingtransversely of the series of leaching vats 12 and having a dischargeend 28 above the shuttle conveyor 20. The feed conveyor 26 is shiftabletransversely of the series of leaching vats 12 on tracks 30, again bestshown in FIG. 2. Both the shuttle conveyor 20 and the feed conveyor 26are preferably belt conveyors having upper runs supported by troughingrolls, once more as best shown in FIG. 2 of the drawings.

The feed conveyor 26 receives a stream of the desired material from atripper 32 associated with the upper run of a supply conveyor 34 of thetroughed belt type which extends the full length of the series ofleaching vats 12 along one side thereof. The tripper 32 is carried bylongitudinal traclts 36 and is movable along such tracks with thematerial depositing apparatus 16, being connected thereto by aninterconnecting means designated generally by the numeral 38 in FIG. 3of the drawings. Thus, as the material depositing apparatus 16 of theinvention moves longitudinally of the series of leaching vats 12, andlongitudinally of any vat in such series, the tripper 32 automaticallymoves longitudinally therewith to maintain a continuous flow of thematerial from the supply conveyor 34 to the feed conveyor 26, and thenceto the shuttle conveyor 20. If desired, additional details as to theforegoing structure may be obtained from my aforementioned copendingapplication, the disclosure of the latter being incorporated herein byreference the same as if it were fully set forth herein.

Considering the shuttle conveyor 21) in more detail, it may be driven ina direction to discharge the material from the end 42 thereof, as shownin F168. 5 and 6, or the end 44 thereof, as shown in FIGS. 7 and 8. Whenshuttle conveyor 26) is driven in a direction to discharge material fromthe end 42 thereof, the shuttle conveyor is shifted laterally ortransversely back and forth between first and second positions,respectively shown in F165. 5 and 6. In its first position, the shuttleconveyor 20 discharges material adjacent one side 46 of the leaching vat12 being charged, as shown in FIG. 5 of the drawings. When the shuttleconveyor 20 is in its second position, it discharges material adjacentthe center of the leaching vat 12, as shown in FIG. 6.

The shuttle conveyor 20 is also laterally or transversely displaceableor shiftable between third and fourth positions,

respectively shown in FIGS. 7 and 8, when it is driven in a directionsuch that is discharges material from the end 44 thereof. When theshuttle conveyor 20 is in its third position, it discharges materialadjacent the opposite side 48 of the vat 12, as shown in FIG. 7. Whenthe shuttle conveyor is in its fourth position, it discharges material,from the end 44 thereof, adjacent the center of the vat 12, as shown inFIG. 8. The second and fourth positions of the shuttle conveyor 20 arelaterally separated sufficiently that the material deposits dischargedfrom the ends 42 and 44 of tee shuttle conveyor do not overlap, as willbe clear from FIGS. 7 and 8.

The feed conveyor 26 has an inlet end 52 which receives a stream ofmaterial from the tripper 32, and has its discharge end 28 located abovethe shuttle conveyor 20 in all positions of the latter. The feedconveyor 26 is also laterally or transversely shiftable between firstand second positions, the first position being shown in FIGS. 5 and 6and the second in FIGS. 7 and 8. When the feed conveyor 26 is in itsfirst position, the discharge end 28 thereof is located on the oppositeside of the center of the vat 12 from the discharge end 42 of theshuttle conveyor 20. Similarly, when the feed conveyor 26 is in itssecond position, as shown in FIGS. 7 and d, its discharge end 28 is onthe opposite side of the center of the vat 12 from the discharge end 44of the shuttle conveyor 20. With this construction, the shuttle conveyor20 may discharge material immediately adjacent the center of the vat 12in its second and fourth positions, as shown in FIGS. 6 and 8 of thedrawings.

The shuttle and feed conveyors 20 and 26 may be driven and shiftedtransversely back and forth, as hereinbefore described, in any suitablemanner. Consequently, it is unnecessary to specifically describe hereinany driving and shifting means for these conveyors. Similarly, thematerial depositing apparatus 16 and the tripper 32 may be displaced orshifted longitudinally of each vat 12, step by step, in any suitablemanner, it therefore being unnecessary to specifically describe anylongitudinal displacing or shifting means for these components.

As will be apparent from FIGS. 5 and 6 of the drawings, when the shuttleconveyor 21) is driven in such a direction that the end 412 thereof isits discharge end, it deposits material in the right half of the vat 12,as viewed in FIGS. 4 to 8 of the drawings. Conversely, when the shuttleconveyor 20 is driven in such a direction that the end 44 thereof is itsdischarge end, it deposits material in the left half of the vat 12,again as viewed in FIGS. 4 to 8 of the drawings. This mode of operationis used in conjunction with step-by-step longitudinal shifting of thematerial depositing apparatus 16, and the tripper 32, in such a way asto deposit a shallow layer of material on the bottom surface of the vat12, first on the right half of the vat bottom, proceeding longitudinallyin one direction, and then on the left half of the bottom, proceedinglongitudinally in the opposite direction.

Amplifying the foregoing, it will be assumed that the materialdepositing apparatus 16 and the tripper 32 are adjacent what will, forconvenience, be referred to as the front end 56, FIG. 4, of the vat 12being charged. It will also be assumed that the shuttle conveyor is inits first position and is operating to discharge material over the end42 thereof, as shown in H6. 5. Under these conditions, the shuttleconveyor 20 deposits material in the corner of the vat 12 defined by theside 46 and the end 56 thereof. As the shuttle conveyor 26 depositsmaterial in such corner, it is simultaneously moved to the left, asindicated by the arrows 62 in FIGS. 1 and 5, until it reaches its secondposition, shown in FIG. 6. This results in the deposition of a shallowor thin transverse strip 64, FIG. S, of

material adjacent the front end 56 of the vat 12 and extending from theside 46 thereof substantially to the center of the vat.

The foregoing accomplished, the material depositing apparatus 16 and thetripper 32 are displaced longitudinally of the vat 12 one step, in adirection from the front end 56 of the vat toward the rear end 58thereof, the width of this step being substantially equal to the widthof the transverse strip 64 previously deposited adjacent the front end56 of the vat. Then, the shuttle conveyor 20 is moved to the right, asindicated by the arrows 66 in FIGS. 4 and 6, so that the shuttleconveyor deposits, from its discharge end 42,'another transverse strip68 of material extending substantially from the center of the vat 12 tothe side 46 thereof and lying alongside the previously depositedtransverse strip 64.

The foregoing process is repeated until the entire right half of thebottom of the vat 12, as viewed in the drawings, is covered with aseries of longitudinally spaced transverse strips of material. In otherwords, the shuttle conveyor 20 is constantly shuttled back and forthbetween its first and second positions while running in a direction todischarge material over the end 42 thereof, and, each time the shuttleconveyor 20 arrives at its first or second position, the materialdepositing apparatus 16 and the tripper 32 are advanced longitudinallyof the vat 12 one step, in a direction from the front end 56 of the vattoward he rear end 58 thereof. Ultimately, the entire right half of thebottom of the vat 12, as viewed in FIGS. 4 to 8 of the drawings, iscovered with transverse strips of material in side-by-side relation.

The same process is then carried out over theleft half of the bottom ofthe vat 12, except that the longitudinal step-by-step displacement ofthe material depositing apparatus 16 and the tripper 32 takes place fromthe rear end 58 of the vat toward the front end 56 thereof. Moreparticularly, as shown in FIGS.

4 and 7, the shuttle conveyor 20 is now driven in a direction todischarge from the end 44 thereof, with the end 44 above the comerdefined by the side 48 and the rear end 58 of the vat 12. Uponsubsequent transverse movement of the shuttle conveyor 20 in thedirection indicated by the arrows 70 in FIGS. 4 and 7, a transversestrip 72 of material is deposited adjacent the left half of the rear end58 of the vat 12, between the side 48 thereof and the center of the vat.Next, the material depositing apparatus 16 and the tripper 32 areadvanced longitudinally one step toward the front end 56 of the vat l2,and the direction of shuttling displacement of the shuttle conveyor 20is reversed, as indicated by the arrows 74 in FIGS. 4 and 8. Thisresults in the deposition of another transverse strip on the left sideof the bottom of the vat l2, alongside and forwardly of the previouslydeposited strip 72. Repeating these operations results in covering theleft half of the bottom of the vat 12 with a plurality of transversestrips of material in the same manner as the right half of the bottom ofthe vat was covered.

When the bottom of the vat 12 has been completely covered with suchtransverse strips of material, each extending substantially half wayacross the vat, the material depositing apparatus 16 and the tripper 32are once again adjacent the front end 56 of the vat 12. At this stage,the various components are returned to the positions shown in FIG. 5,whereupon the foregoing operations are repeated to deposit a secondlayer of transverse strips of material on top of the first. Theseoperations are repeated as many times as required to produce the numberof layers of material necessary to fill the vat l2 to'the desired level.

In forming the various transverse strips of material constituting eachlayer in the vat 12, the material is preferably deposited to a depth ofonly of the order of 6 to 24 inches. Consequently, in forming transversestrips to a depth of this order of magnitude, there is substantially noopportunity for any fines present to separate from coarser particles toany significant extent. The end result is that the vat 12 is charged tothe desired level with a uniform, substantially homogeneous mass ofmaterial with no concentrations of fines of sufficient volumes to beimpenetrable by a leaching liquid, or other treating liquid.Consequently all portions of the total char e in the vat 12 aresubstantially uniformly contacted by t e treating liquid which is theessential feature of the invention.

Although an exemplary embodiment of the invention as been disclosedherein for purposes of illustration, it will be understood that variouschanges, modifications and substitutions may be incorporated in suchembodiment without departing from the spirit of the invention, asdefined by the claims appearing hereinafter.

I claim:

1. A method of uniformly depositingmaterial on a surface havingtransversely spaced sides and longitudinally spaced ends, including thesteps of:

a. depositing a first transverse strip of material on one-half of saidsurface, adjacent one end of said surface, in a direction from one sideof said surface to the center of said surface;

b. then depositing a second transverse strip of material on said onehalf of said surface, alongside said first transverse strip previouslydeposited on said one half of said surface and between such firsttransverse strip and the other end of said surface, in a direction fromthe center of said surface to said one side of said surface;

. c. then repeating the steps of subparagraphs (a) and (b) untiladditional transverse strips of material have been deposited on said onehalf of said surface in side-by-side relation all the way to said otherend of said surface;

d. then depositing a first transverse strip of material on the otherhalf of said surface, adjacent said other end of said surface, adjacentsaid other end of said surface, in a direction from the other side ofsaid surface to the center of said surface;

e. then depositing a second transverse strip of material on said otherhalf of said surface, alongside said first transverse strip previouslydeposited on said other half of said surface and between such firsttransverse strip and said one end of said surface, in a direction fromthe center of said surface to said other side of said surface; and

. then repeating the steps of subparagraphs (d) and (e) until additionaltransverse strips of material have been deposited on said other half ofsaid surface in side-by-side relation all the way to said one end ofsaid surface.

2. A method of uniformly depositing material on a surface havingtransversely spaced sides and longitudinally spaced ends, characterizedby the use of a bidirectional shuttle conveyor above and extendingtransversely of said surface and shiftable transversely of said surfacebetween first and second positions wherein one end of said shuttleconveyor is adjacent one side of said surface and the center of saidsurface, and between third and fourth positions wherein the other end ofsaid shuttle conveyor is adjacent the other side of said surface, andthe center of said surface, and including the steps of:

a. driving said shuttle conveyor in a direction to discharge materialfrom said one end thereof;

b. transversely shifting said shuttle conveyor back and forth betweenits first and second positions while driving it in said direction;

c. shifting said shuttle conveyor longitudinally of said surface fromone end thereof to the other in a step-by-step manner as said shuttleconveyor is shified into its first and second positions while beingdriven in said direction;

d. then driving said shuttle conveyor in the other direction todischarge material from the other end thereof;

e. transversely shifting said shuttle conveyor back and forth betweenits third and fourth positions while driving it in said other direction;and

f. shifting said shuttle conveyor longitudinally of said surface fromsaid other end thereof to said one end thereof in a stepby-step manneras said shuttle conveyor is shifted into its third and fourth positionswhile being driven in said other direction.

1. A method of uniformly depositing material on a surface havingtransversely spaced sides and longitudinally spaced ends, including thesteps of: a. depositing a first transverse strip of material on one-halfof said surface, adjacent one end of said surface, in a direction fromone side of said surface to the center of said surface; b. thendepositing a second transverse strip of material on said one half ofsaid surface, alongside said first transverse strip previously depositedon said one half of said surface and between such first transverse stripand the other end of said surface, in a direction from the center ofsaid surface to said one side of said surface; c. then repeating thesteps of subparagraphs (a) and (b) until additional transverse strips ofmaterial have been deposited on said one half of said surface inside-by-side relation all the way to said other end of said surface; d.then depositing a first transverse strip of material on the other halfof said surface, adjacent said other end of said surface, adjacent saidother end of said surface, in a direction from the other side of saidsurface to the center of said surface; e. then depositing a secondtransverse strip of material on said other half of said surface,alongside said first transverse strip previously deposited on said otherhalf of Said surface and between such first transverse strip and saidone end of said surface, in a direction from the center of said surfaceto said other side of said surface; and f. then repeating the steps ofsubparagraphs (d) and (e) until additional transverse strips of materialhave been deposited on said other half of said surface in side-by-siderelation all the way to said one end of said surface.
 2. A method ofuniformly depositing material on a surface having transversely spacedsides and longitudinally spaced ends, characterized by the use of abidirectional shuttle conveyor above and extending transversely of saidsurface and shiftable transversely of said surface between first andsecond positions wherein one end of said shuttle conveyor is adjacentone side of said surface and the center of said surface, and betweenthird and fourth positions wherein the other end of said shuttleconveyor is adjacent the other side of said surface, and the center ofsaid surface, and including the steps of: a. driving said shuttleconveyor in a direction to discharge material from said one end thereof;b. transversely shifting said shuttle conveyor back and forth betweenits first and second positions while driving it in said direction; c.shifting said shuttle conveyor longitudinally of said surface from oneend thereof to the other in a step-by-step manner as said shuttleconveyor is shifted into its first and second positions while beingdriven in said direction; d. then driving said shuttle conveyor in theother direction to discharge material from the other end thereof; e.transversely shifting said shuttle conveyor back and forth between itsthird and fourth positions while driving it in said other direction; andf. shifting said shuttle conveyor longitudinally of said surface fromsaid other end thereof to said one end thereof in a step-by-step manneras said shuttle conveyor is shifted into its third and fourth positionswhile being driven in said other direction.